In the city of Los Angeles, 64 percent of homicides between 1999 and 2003 were committed with a handgun.[1] Although federal law prohibits ownership of firearms and ammunition by juveniles and certain people who may be prone to violence,
unregulated secondary markets offer opportunities for these people to acquire them.

Many "crime guns" move quickly from legal sale into criminal use. Research has shown that one of every five guns that is used in a crime in Los Angeles moves very quickly from its initial,
legal sale into criminal use.[2] This suggests that many legal gun purchases in the city might be what are called "straw purchases" — that is, a gun bought
by an adult with a clean record expressly to give or sell it to someone who could not have otherwise gotten one.

Intervening in illegal gun markets could reduce criminals' access to guns. In 2001, an NIJ-funded project took a data-driven approach to understanding and disrupting these illegal gun markets in Los
Angeles. The researchers hoped that intervening in these markets could help to reduce gun violence.

In their final report, the researchers argue that disrupting the illegal market in guns could have a real effect on gun violence.
Contrary to commonly held belief, they say, high-crime areas are not awash in guns: Studies have shown that most robbers do
not use guns[3] and most youths who are in gangs or who commit crimes do not own one.[4] By learning how guns move into the wrong hands, police and policymakers could make guns more difficult to access by those
who will use them for harm.

About the Research

The project first created a data-analysis software tool and workstation for the new Southern California Regional Crime Gun
Center, run by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). The prototype system was designed to help crime
analysts better detect patterns in firearm-trace data that could indicate trafficking. The system integrated different ATF
data sources and overlaid an interface through which analysts could manipulate the data to check for indicators of trafficking,
illegal sales or other suspicious activity. It also provided analysts with a system to report potential leads for investigation.

Using the prototype system to reconstruct the movement of crime guns in the county, analysts found a surprising result: Although
law enforcement officers in Los Angeles believed that most guns being used by local criminals had been brought in from neighboring
states with fewer firearms regulations, the data showed that most crime guns were actually purchased originally from in-county,
licensed dealers. In fact, there was often only a few miles between the home address of the original purchaser of a gun and
that of the gun's possessor at the time it was recovered by police.

In reviewing these data, an interagency working group (composed of ATF officials, criminal justice researchers, law enforcement,
prosecutors and other stakeholders) suspected that straw purchases were driving these outcomes. The working group designed
an intervention, described in the next section (Intervening in Gun Markets) meant to make these "straw buyers" think twice about illegally transferring their guns.

The interagency working group was also concerned about potential illegal markets for ammunition. Researchers designed a study,
described on the page Criminal Purchase of Firearm Ammunition, to determine whether prohibited individuals were buying ammunition from dealers, and if so, where and what they were buying.

Intervening in Gun Markets

In Los Angeles, which has a high rate of gun-related crime, research has shown that many crime guns move relatively quickly
— and over relatively short geographic distances - from their original, legal purchase to recovery by law enforcement. (See
Strategies for Disrupting Illegal Firearms Markets: A Case Study of Los Angeles. This suggests that many guns used by criminals are given or sold to them by straw buyers. Criminal justice theory suggests
that people like these straw buyers — who have little, if any, criminal history — are more easily deterred by risks of arrest
and prosecution than are those with criminal histories. A working group composed of law enforcement, academics, and other
stakeholders in Los Angeles designed a letter campaign designed to remind potential straw buyers of their legal responsibility
to transfer their gun legally and that the state had a record connecting that gun to them.

About the Research

Two separate areas of Los Angeles, with a total population of 425,000 people, were included in the letter program. The working
group chose these areas because they have large numbers of residents who legally buy guns that later are used in crimes by
others.

For about a year in 2007 and 2008, researchers sent letters to residents of these areas who initiated gun purchases on odd-numbered
days. (People who initiated purchases on even numbered days didn't receive the letter, for comparison purposes.) The letters
outlined the problem of gun violence in the city and reminded recipients of their legal responsibilities as gun owners. Specifically,
the letters informed recipients that it was a crime to sell or give a gun to someone without completing a dealer record of
sale form. They also warned recipients that they could be prosecuted if they did not do so and the gun was later used in a
crime.

Each would-be purchaser received their letter during the legally mandated 10-day waiting period before they could return to
the dealer and pick up their new gun. For 22 months afterwards, researchers tracked the outcomes of the transactions.

The researchers found one difference between the group that received letters and the group that had not: Those who received
the warning letter were much more likely to report that their guns had been stolen than those who hadn't. The researchers
suggest that the letter may have caused this outcome in two different ways - by motivating more law-abiding people to report
real thefts of their new guns or by inspiring straw buyers to falsely report thefts after an illegal transfer in order to
protect themselves.

The researchers point out that only 13 percent of crime guns uncovered around the time of the study had been bought in the
past two years. They suspect that a greater period of monitoring would have revealed a more pronounced effect of the letter
on firearms trafficking.